1. Field of the Invention
The present invention relates to a device and method for collection of oil and gas from an underwater source, and particularly but not exclusively, to the collection and recovery of oil from undersea leakages.
2. Description of the Prior Art
Modern engines and turbines are often powered by oil, diesel or other oil derivatives. Further, oil derivatives are also used as lubricants and to generate heat. Thus, oil extraction is significantly important to our way of living. Oil is a hydrocarbon found in pockets in the Earth's crust which is commonly referred to as crude oil. Obtaining oil is difficult as it involves finding these pockets which also contain gases and extracting the oil therein without causing the oil to simply pour out as a result of pressure differentials. As oil comprises complex hydrocarbons which take thousands of years to develop by a chemical and mechanical process, the existing reservoirs are effectively the only supply of oil readily available. Thus, oil is a significantly valued commodity.
Oil-containing reservoirs can be located under dry land or underwater. Submarine oil extraction is particularly difficult because the entire process is further constrained by the environment. Moreover, leaks resulting from the extraction process are very harmful to marine ecosystems because oil chemicals are toxic to marine organisms and birds; further, as oil has a high viscosity, marine animals and birds become coated in oil if they happen to be on a leak site. Currently, there are no methods which are guaranteed to contain or clear an underwater oil leak. Further, current methods focus on containing or mitigating environmental damage but are not suitable to prevent wastage of the leaked substance, i.e. collect and recover oil and gas, and, in addition, contain or mitigate environmental damage.
For example, a sub-sea oil recovery system is known which comprises a rigid cap structure which, in use, is placed over a leak to collect hydrocarbons from a leaking well. The structure comprises lines connected to a pump which pumps the leaking oil into a vessel on the water surface. The collected substances can then be separated by additional methods. Although, this method is effective in shallow leak sources it is not suitable from a practical point of view for use in deep waters.